Additive manufacturing is a process of creating three-dimensional components by depositing overlapping layers of material under the guided control of a computer. One technique of additive manufacturing is known as material extrusion. Using the material extrusion technique, a matrix material (e.g., a heated and/or pressurized thermoplastic) is extruded through a print head. The print head is moved in a predefined trajectory (a.k.a., a tool path) as the matrix material discharges from the print head, such that the matrix material is laid down in a particular pattern and shape of overlapping layers. The matrix material, after exiting the print head, hardens into a final form.
Although the material extrusion technique and other techniques of additive manufacturing can be efficient ways to produce high-performance and geometrically complex original components, similar looking copies of the component can be easily produced using commercially available printers. In particular, the original components can be scanned to generate data files that represent external features of the original components. These data files can then be fed into the commercially available printers and used to produce copies that appear to be identical to the original components. In some instances, the copies may even be marked, packaged, and/or sold as original components.
The copies, while they may appear identical, may not have identical internal structure or materials or be produced in a manner identical to that (e.g., using an identical tool path) used to produce the original components. As result, the copies may not perform as well as the original components. In addition, the copies may be produced illegally (e.g., without licensed authority from the manufacturer) and, because the copies may appear to be identical to and are sold as the original components, customers may unknowingly purchase the copies in place of the original components. The illegal production and sale of copied components can undercut the market of original components. And when the copies fail prematurely, the customers may attempt to receive undue warranty relief. In some situations, it may be difficult for the manufacture to determine if a failed component is an original or a copy.
Historically, printed components have been fabricated to include hidden anti-counterfeit features that can be used to determine if a given component is an original or a copy. In particular, information about the component was printed onto an intermediate layer inside the part. The information included, for example, a manufacturer's name or logo, an alpha-numeric part number, or other information. Then, when the authenticity of a given component was questioned, that component could be cut open at the intermediate layer to see if the anti-counterfeit features were included.
While the traditional approach to preventing counterfeit printing of components may be somewhat successful, it can also be problematic. In particular, it may be difficult to determine where the part should be cut open to find the corresponding anti-counterfeit features. In addition, the anti-counterfeit features can interrupt a continuous structure of the component, creating weak points in the component. Similarly, voids created in and around these features e.g., between letters, numbers, and/or images) may create weak points in the component. Finally, some traditional anti-counterfeit features may, themselves, be easy to copy once their existence within the component is determined.
The disclosed method and component are directed to overcoming one or more of the problems set forth above and/or other problems of the prior art,